window balances missing from lower pane

Hi i recently purchashed a set of series 500 balances. i measured the top balances as a starting point. 21" is the top balances lengthes for the top pane so i ordered that size. The brackets were missing as well so i picked the style that closely matched the brackets on the top which were two diff styles on the same window( go figure).

When i installed them today i had difficulty installing the balance thru the bracket (17-083) and the balances were 3 3/4 to short from where they should but up against the top of the window frame so after wrestling to get the spiral tip end thru the bracket and installing the balances is when i noticed that i have the wrong application

is it possible To return them for a diff style shoe and longer balances once they are installed?

Here is a photo of my set up as it is with the shorter balances they are doing the job but i feel they should be to the top like the other windows in the home.

Yea i think so cuz the end of the spiral sticks out the bottm of the window not allowing it to fully close and latch.

If i measure the glass its about 21" and both panes are equal in height. But like a mentioned the balance fully extended with the window closed leaves me about 3 3/4 short of where it should be

that shoe you suggested and a 24" balance should do the trick can i send the other set back for refund?